The present invention relates to a method and to a system for aiding the navigation of an aircraft, including a transport aircraft.
It is known that the majority of accidents or incidents involving an aircraft occur during phases of movement on an airfield, and in particular the following incidents:                runway incursions;        runway excursions;        taxiway excursions; and        collisions between aircraft, or between an aircraft and an airfield facility (a building, for example).        
To solve these safety problems, there is known a system for aiding airport navigation, of a type known as OANS (On-board Airport Navigation System), which has its own database and takes over from the flight management system (FMS) on the navigation screen, known as ND (Navigation Display), to assist pilots in the tasks of preparing for and executing arrival on an area of ground. The main function of this OANS system is to display a dynamic map of the airport, of a type known as AMM (Airport Moving Map), which is oriented and positioned according to the location of the aircraft shown on it.
To change from one system to the other, in other words, from the display of flight navigation data (FMS) to the display of ground navigation data (OANS), on the ND screen, the pilot has to select a particular scale that allows him to view the AMM map instead of the flight plan from the FMS system, and to access the ground functions that enable him to prepare for arrival. This separation between the two systems, from an architectural point of view with separate databases, but also in terms of display, therefore introduces a discontinuity between the flight phases (approach) and the ground phases (landing), a break in the representation of the trajectory (both in terms of content and of display logic and interaction logic), and also a temporary loss of information for the pilot. The pilot must therefore construct for himself a mental representation of the trajectory from the current position to the final position, for example an airline's parking place.
Furthermore, while preparing for arrival on the ground using the ND screen, the pilot must refer to navigation maps such as the en route maps, maps for the standard departure or arrival procedure and for the departure procedure in the event of engine failure, known as SID (Standard Instrument Departure) and STAR (Standard Terminal Arrival Routes), approach maps, and maps of airports and taxiways. On some aircraft, pilots carry these navigation maps in their flight bag, which also contains the operations manuals, the flight manual, the checklists, and the performance data. On other aircraft, in order to make the bags carried by pilots lighter, this data (the navigation maps and also the different documents mentioned above) are available via an electronic system known as EFB (Electronic Flight Bag), which can be connected to the avionics systems. From document US 2012/0035849, there is known a flight information display device, comprising an information processing system that has a flight management computer and an EFB type of electronic system. In the standard forms of architecture, the EFB applications focus on the transition between the paper and the digital, and therefore restrict themselves to providing identical reproductions of the paper versions while adding a few functions to these, in order to minimize the time required to learn how to use this technology. The changes between the paper versions and digitized versions of the navigation maps are therefore minimized to facilitate the process of standardization and certification.
In both cases (paper or digital maps), the items of information presented are additional to those available on the ND screen: some items of information shown on the maps are not displayed on the ND screen and vice versa. This separation is found at an architectural level, because two databases (the FMS database and the maps database) coexist in the cockpit without communicating.
From the pilot's point of view, this emphasizes a second form of discontinuity in terms of sources and displays of navigation information. This is because he must constantly switch from one medium to the other and construct a mental picture of the situation by combining the information required to manage the aircraft's trajectory. In addition, each pilot constructs his own representation of the situation, which can lead to potential divergences between two members of the same crew.
This complex standard architecture, which has discontinuities, produces a significant workload for the crew.